Cancer benchmark levels for a number of chemicals in food were exceeded by children in self-reported dietary data, according to a study.

Researchers at the University of California, Davis (UC Davis) and University of California, Los Angeles (UCLA) measured foodborne toxin exposure in children and adults by pinpointing foods with high levels of toxic compounds and determining how much was consumed.

All 364 children in the study exceeded cancer benchmarks for arsenic, dieldrin, DDE and dioxins and more than 95% of preschool children exceeded non-cancer risk levels for acrylamide.

Food may be the primary route of exposure to contaminants from packaging, organic pollutants and pesticides, said the study published in the journal Environmental Health.

External influences

The way in which food is cooked, processed, and packaged may introduce bisphenol A, phthalates, and acrylamide that are not present in raw food, noted the authors.

The researchers suggested dietary strategies to reduce exposure such as consuming less animal foods (meat, dairy, and fish) to reduce intake of organic pollutants and metals, and lower quantities of chips, cereal, crackers, and other processed carbohydrate foods to reduce acrylamide intake.

Cancer benchmark levels were derived from databases including the Total Diet Study and risk was assessed by comparing it to toxin consumption.

The data used is an abbreviated version based on a telephone survey in 2007 and the team admitted the study could have resulted in “under and over estimation”.

“Previous research suggests that dietary survey respondents are inclined to over-report healthy foods and under-report unhealthy foods,” they added.

Risk method

The researchers estimated exposure to multiple food contaminants based on dietary data from 207 preschool-age children (2-4 years), 157 school-age children (5-7 years), 446 parents of young children and 149 older adults.

Based on this data, the greatest exposure to pesticides from foods included in the analysis were tomatoes, peaches, apples, peppers, grapes, lettuce, broccoli, strawberries, spinach, dairy, pears, green beans, and celery.

Irva Hertz-Picciotto, professor and chief of the Division of Environmental and Occupational Health at UC Davis, said contaminants get into food in a variety of ways.

"They can be chemicals that have nothing to do with the food or byproducts from processing. We wanted to understand the dietary pathway pesticides, metals and other toxins take to get into the body."

The researchers recommended future studies ask about each food items individually to increase accuracy of analysis and look at the interaction of the foodborne toxins in the body.

“Further studies are needed to understand the synergistic effects of exposure to multiple dietary toxins, the variability of cumulative dietary toxic exposure…and the best approaches to limiting exposure to multiple compounds and from multiple routes.”